Two-year mortality after transcatheter aortic valve implantation versus medical therapy for high-surgical risk or inoperable aortic stenosis patients.

BACKGROUND AND AIM OF THE STUDY: Transcatheter aortic valve implantation (TAVI) has become a therapeutic option for the treatment of high-risk or inoperable patients with symptomatic severe aortic stenosis. The study aim was to compare the two-year mortality of high-risk or inoperable patients treated by TAVI compared to medical therapy, in a single-center setting. METHODS: A total of 135 consecutive patients (58 males, 77 females; mean age 80 +/- 6 years; logistic EuroSCORE 21 +/- 13%) who had undergone TAVI was compared to 135 patients (60 males, 75 females; mean age 79 +/- 3 years; logistic EuroSCORE 21 +/- 19%) who had undergone medical treatment before TAVI became available. The one- and two-year follow up mortalities were recorded for each group. In the TAVI group, the patient characteristics were analyzed for predictors of mortality. RESULTS: Sixteen patients (12%) in the TAVI group and 10 (7%) in the medically treated group died within 30 days of intervention or presentation (p = 0.303). At the one-year follow up, 28 TAVI patients (21%) and 69 medically treated patients (41%) died (p < 0.001). At the two-year follow up, 41 TAVI patients (30%) and 80 medically treated patients (59%) died (p < 0.001). Log-rank analysis demonstrated a significant survival benefit after TAVI compared to medical treatment during the total follow up period. Univariate predictors of death at the two-year follow up included medical therapy, logistic EuroSCORE, and pulmonary hypertension. Medical therapy remained the only independent predictor of two-year mortality in a multivariate analysis (OR 3.343; 95% CI 2.021-6.234, p < 0.001). CONCLUSION: In high-surgical risk or inoperable symptomatic aortic stenosis patients, the one- and two-year follow up mortalities of patients treated with TAVI was significantly lower than after medical therapy. Predictors of mortality, in addition to treatment strategy, were pulmonary hypertension and EuroSCORE.

Electrocardiographic and imaging predictors for permanent pacemaker requirement after transcatheter aortic valve implantation.

BACKGROUND AND AIM OF THE STUDY: Pacemaker (PM) implantation is a possible requirement after transcatheter aortic valve implantation (TAVI). The study aim was to evaluate the electrocardiographic and imaging predictors of the need for PM implantation after TAVI. METHODS: A total of 80 consecutive patients (mean age 82 +/- 6 years) who had been referred for TAVI were included in the study. Transfemoral TAVI was performed in 58 patients (CoreValve ReValving; 72%), while 22 patients (28%) underwent transapical TAVI using the Edwards SAPIEN valve. Patient characteristics, and the frequency of atrioventricular (AV) block, right bundle branch block (RBBB) and left bundle branch block (LBBB), were evaluated for the prediction of PM implantation after TAVI. In addition, the severity and distribution of aortic valve calcification (AVC) were assessed by calculating the Agatston AVC score for the total aortic valve, as well as for each cusp, using dual-source computed tomography. RESULTS: Pre-procedural RBBB was present in six patients (8%), while eight patients (10%) showed pre-procedural LBBB. In 20 of the 80 patients (25%), a new LBBB was observed after TAVI. In 17 TAVI patients (21%; only CoreValve patients) there was an indication for permanent PM implantation that was related to complete AV block (n = 13) or complete RBBB or LBBB with AV delay (n = 4). Four of six patients (67%) with pre-procedural RBBB received a PM after TAVI. Multivariate logistic regression analysis revealed that only prosthesis type (r = 0.30, p = 0.01) and pre-procedural RBBB (r = 0.4, p = 0.02) were significantly associated with the need for permanent PM implantation after TAVI. CONCLUSION: TAVI is frequently associated with new conduction disturbances. A higher incidence of new LBBB and of permanent PM requirement occurred with the CoreValve ReValving system. There was no relationship between the severity or distribution of AVC and the need for PM implantation after TAVI. Patients with pre-procedural RBBB are deemed to be at risk for PM implantation after TAVI.

Impact of a new conduction defect after transcatheter aortic valve implantation on left ventricular function.

OBJECTIVES: This study sought to evaluate the impact of new conduction defects after transcatheter aortic valve implantation (TAVI) on the evolution of left ventricular (LV) function during 1-year follow-up. BACKGROUND: New left bundle branch block (LBBB) or need for permanent pacing due to atrioventricular (AV) block are frequent after TAVI. METHODS: A total of 90 consecutive patients treated with TAVI and who had 12-month echocardiographic follow-up were included in the study. In 39 patients, a new conduction defect (new LBBB or need for permanent pacemaker activity.) persisted 1 month after TAVI. In 51 patients, no persistent new conduction defect was observed. Two-dimensional echocardiography using parasternal short-axis, apical 4-chamber, and apical 2-chamber views was performed before TAVI and at 1-year follow-up to determine LV volumes and ejection fraction based on Simpson's rule. Speckle-tracking echocardiography was applied using standard LV short-axis images to assess the effect of new conduction defects on time-to-peak radial strain of different LV segments as a parameter of LV dyssynchrony. RESULTS: New conduction defects resulted in marked heterogeneity in time-to-peak strain between the 6 analyzed short-axis segments. During 1-year follow-up after TAVI, there was a significant increase in left ventricular ejection fraction (LVEF) in patients without new LBBB (53 ± 11% pre TAVI to 59 ± 10% at follow-up; p < 0.001), whereas there was no change in LVEF in patients with a new conduction defect (52 ± 11% pre TAVI to 51 ± 12% at follow-up, p = 0.740). Change in LV end-systolic volume was also significantly different between patient groups (-1.0 ± 14.2 vs. -11.2 ± 15.7 ml, p = 0.042). New conduction defect and LVEF at baseline were independent predictors of reduced LVEF at 12-month follow-up after TAVI. CONCLUSIONS: LVEF improves after TAVI for treatment of severe aortic stenosis in patients without new conduction defects. In patients with a new conduction defect after TAVI, there is no improvement in LVEF at follow-up.

Incidence and predictors of left bundle branch block after transcatheter aortic valve implantation.

OBJECTIVE: The aim of this study was to evaluate the frequency and predictors of left bundle branch block (LBBB) after Transcatheter Aortic Valve Implantation (TAVI) using CoreValve and Edwards SAPIEN prosthesis. METHODS: 154 consecutive patients (53 male, mean age 81 ± 7 years) with severe symptomatic aortic stenosis underwent TAVI. Transfemoral AVI (CoreValve) was performed in 72 patients (47%). Transapical AVI (Edwards SAPIEN valve) was done with in n=82 patients (53%). Patient characteristics, valvular and left ventricular outflow tract geometry from pre- and postprocedural imaging (computed tomography, transesophageal echocardiography and callipered angiography) and procedural characteristics were evaluated to define predictors of new LBBB after TAVI. PATIENTS: Preprocedural LBBB was present in 15 patients (n=5 CoreValve, n=10 in Edwards SAPIEN). In 40 of 139 patients (29%) a new LBBB was observed after TAVI. The frequency of new LBBB was higher with CoreValve n=27 (38%) than with Edwards SAPIEN implantation n=13 (16%; p=0.006). Patients with new LBBB had larger valve implantation depth into the left ventricular outflow tract (9.0 ± 2.9 vs. 4.4 ± 2.5mm, p<0.001). In 18 of 40 patients (45%) the new LBBB was persistent at 30days. Predictors of new LBBB were prosthesis implantation depth into the left ventricular outflow tract (OR=1.185 95% CI 1.064-1.320 per additional mm implantation depth; p=0.002) and use of CoreValve prosthesis (OR=2.639 95% CI 1.314-5.813; p=0.007). CONCLUSION: TAVI is frequently associated with new LBBB. There is a higher frequency of persistent LBBB with the CoreValve system. Implantation depth is a critical factor for the development of new LBBB.

Thirty-day outcome after transcatheter aortic valve implantation compared with surgical valve replacement in patients with high-risk aortic stenosis: a matched comparison.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has become a therapeutic alternative to surgery for the treatment of severe aortic stenosis in high-surgical risk patients. The aim of this study was to compare 30-day mortality of high-risk patients treated by TAVI versus surgical aortic valve replacement. METHODS: A total of 175 patients (60 men; mean age, 80±6 years; Euroscore 21±13%) having undergone TAVI were compared with 175 matched patients (76 men; mean age, 79±3 years; Euroscore 17±9%), which have undergone conventional aortic valve replacement and were deemed to be high-risk patients by the cardiothoracic surgeons. Thirty-day mortality and major adverse events were recorded in both groups. Patients' characteristics were analyzed for predictors of mortality in the TAVI group. RESULTS: Twenty-one patients (12%) in the TAVI group and 13 patients (8%) in the surgical group died within 30 days of the procedure (P=0.165). Two patients (1%) in the TAVI group and one patient (0.5%) in the conventional surgery group had a major stroke (P=1.0). Seven patients (4%) in the TAVI group and 25 patients (14%) in the conventional surgery group required dialysis post procedure (P=0.0013). The average length of stay in the intensive care unit was lower in the TAVI group compared with the conventional surgical group (3.3±3.1 vs. 6.6±10.5 days; P<0.001). Age was the only independent predictor of mortality in the TAVI group (odds ratio=1.009; 95% confidence interval: 1.001-1.018 per additional year; P=0.0186) and in the total study population (odds ratio=1.007; 95% confidence interval: 1.001-1.013 per additional year; P=0.0186). CONCLUSION: In high-surgical risk patients, TAVI can be performed at a mortality risk comparable with conventional surgery with a reduced length of post interventional intensive care unit stay and less need for dialysis.

Debulking prior to stenting--a worthwhile effort?

The rationale of debulking prior to stenting is to improve acute and long-term results of complex lesion angioplasty by reduction of plaque burden and/or reduction of calcified material prior to stenting, thus, allowing subsequent optimized stent-implantation and expansion. There are several registries analyzing the effect of various debulking-strategies prior to stenting in groups of selected patients and in high-risk subgroups. The majority of these studies performed DCA prior to stenting. In summary, these studies showed a reduction in restenosis rates and need for reintervention at long-term follow-up. The total TLR-rate (PCI, CABG) during a mean follow-up of 6 to 14 months is reported to be 4 to 14%; the rate of restenosis is given as 7 to 14%. However, until now, no large scale randomised "debulking prior to stenting" versus "conventional stenting without debulking" study has been published in detail. Several studies suggest benefit for debulking prior to stenting in complex lesion subsets, e.g., total chronic occlusions, ostial lesions, bifurcation lesions and saphenous vein grafts, but as of now, no convincing strategy has evolved.